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Activation energy of bromate/bromide reaction in acidic solution

  1. Mar 10, 2007 #1
    1. given/known data
    My work is about calculating activation energy of bromate/bromide reaction.
    Besides KBr and KBrO3, phenol and methy red is also used. The Bromine produced react rapidly with phenol, once all the phenol is consumed, the bromine will decolorize the methyl orange indicator. In that way the time for a reaction to reach a certain point can be determined

    2. Relevant equations
    BrO3- (aq) + 5 Br- (aq) + 6 H+ (aq) → 3 Br2 (aq) + 3 H2O (l)

    My question is, what is the gel-like substances i found at the end of the reaction?
    Last edited: Mar 10, 2007
  2. jcsd
  3. Oct 3, 2007 #2
    a guess

    I would guess that it is 2,4,6TribromoPhenol : http://chemicalland21.com/specialtychem/perchem/2,4,6-TRIBROMOPHENOL.htm
    But then I have a question for you : do you have an experiment guide for the experiment - I found the one from Bangor University, but there is no info about conentrations and so - I would be glad if you could send me a mail if you have it.
    best wishes
  4. Mar 31, 2009 #3
    concentrations for a 3 min reaction are as follows:
    0.01M phenol (0.94g in 1dm3) 70cm3
    0.1M KBr (11.9g to 1 dm3) 35cm3
    0.02M KBr03 (3.34g in 1 dm3) 35cm3
    0.5M H2SO4 35cm3

    hope this helps
  5. Feb 16, 2010 #4
    did you manage to find the activation enthalpy? And when plotting a 1/T against natrual log of rate graph false origins are ok because I only need the gradient?
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